package com.atguigu.cart.interceptor;

import com.atguigu.cart.vo.UserInfoTo;
import com.atguigu.common.constant.AuthServerConstant;
import com.atguigu.common.constant.CartConstant;
import com.atguigu.common.vo.MemberRespVo;
import org.apache.commons.lang.StringUtils;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;
import sun.audio.AudioPlayer;

import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.util.UUID;

/**
 * Data time:2022/4/10 11:29
 * StudentID:2019112118
 * Author:hgw
 * Description: 拦截器
 * 在执行目标方法之前，判断用户的登录状态，并封装传递给controller目标请求
 *  登录用户
 *  临时用户
 */
public class CartInterceptor implements HandlerInterceptor {

    public static ThreadLocal<UserInfoTo> threadLocal = new ThreadLocal<>();

    /**
     * 目标方法执行之前
     * @param request
     * @param response
     * @param handler
     * @return
     *  true:   放行
     *  false:  不放行
     * @throws Exception
     */
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response,
                             Object handler) throws Exception {
        UserInfoTo userInfoTo = new UserInfoTo();
        HttpSession session = request.getSession();
        MemberRespVo member = (MemberRespVo) session.getAttribute(AuthServerConstant.LOGIN_USER);
        if (member != null) {
            // 用户登录
            userInfoTo.setUserId(member.getId());
        }
        Cookie[] cookies = request.getCookies();
        if (cookies!=null && cookies.length>0){
            for (Cookie cookie : cookies) {
                //user-key
                String name = cookie.getName();
                if (name.equals(CartConstant.TEMP_USER_COOKIE_NAME)) {
                    userInfoTo.setUserKey(cookie.getValue());
                    userInfoTo.setTempUser(true);   // 标识携带user-key
                }
            }
        }

        // 如果没有临时用户，则进行分配
        if (StringUtils.isEmpty(userInfoTo.getUserKey())){
            String uuid = UUID.randomUUID().toString();
            userInfoTo.setUserKey(uuid);
        }

        // 目标方法执行之前，将信息封装好放进ThreadLocal
        threadLocal.set(userInfoTo);
        return true;
    }

    /**
     * 目标方法执行之后
     *  分配临时用户，让浏览器保存
     * @param request
     * @param response
     * @param handler
     * @param modelAndView
     * @throws Exception
     */
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        UserInfoTo userInfoTo = threadLocal.get();

        if (!userInfoTo.isTempUser()) {
            // 持续的延长临时用户的过期时间
            Cookie cookie = new Cookie(CartConstant.TEMP_USER_COOKIE_NAME, userInfoTo.getUserKey());
            cookie.setDomain("gulimall.cn");
            cookie.setMaxAge(CartConstant.TEMP_USER_COOKIE_TIMEOUT);
            response.addCookie(cookie);
        }

    }
}
